Precision solder transfer method and means
US4832255A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 25, 1988 |
| Grant date | May 23, 1989 |
| Priority date | — |
| Expiry date | Jul 25, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49213
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
This invention employs a carrier upon which a thin conductive film has been applied. The conductive film is of a metallic material which exhibits a surface energy such that it is not readily wetted by solder. A patterned mask is disposed on the conductive film, with the mask having openings which expose selected areas of the conductive film. Solder is deposited in the mask openings and is weakly adherent to the exposed areas of the conductive film. The carrier is then disposed over and in registration with conductive land areas of a circuit carrier, such that the solder in the mask openings is aligned with the land areas of the circuit carrier. Subsequently, the carrier and circuit land areas are brought into contact, heated, the solder bonded to the lands, and the carrier is lifted away for subsequent reuse. In another species of the invention, a thin film layer of solder is directly deposited on and weakly adherent to a flexible base layer. Subsequently, tool means which registers with the areas to be soldered, presses the base layer/solder combination against the areas to be coated with solder, thereby causing the solder to adhere to the underlying circuit configuration.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.